Some conventional computer input devices include a small number of data entry keys or buttons (e.g., two, eight, or ten keys), rather than the large number (typically more than eighty) on conventional computer keyboards for entering alphanumeric characters. Examples of such input devices include computer user interface hand controllers of interactive cable television (ICTV) set top boxes and interactive multimedia systems, which hand controllers include a small number of data entry buttons (e.g., two, four, eight, or ten buttons).
Other commercially available computer game systems typically include computer input devices having a small number of data entry keys or buttons.
For example, commercially available products known as the Tandy Video Information System multimedia player, and game systems marketed by Nintendo and Sega, include input devices (e.g., game controllers) designed to be held by both hands of a user. Each such input device has two sets of four buttons: one set arranged for manipulation by the right hand of a user, and the other set for manipulation by the user's left hand. By manipulating buttons of this type of input device, a user can input alphanumeric text to a processor programmed with a conventional operating system (such as the Microsoft Modular Windows operating system available from. Microsoft Corporation). The programmed processor of the multimedia player (or game system) displays representations of a large number of available alphanumeric characters, moves a displayed cursor among the displayed characters (in response to button actuations executed by a user of the input device), and enters a character whose representation is "highlighted" by the cursor (in response to user depression of a "selection" button on the input device). However, the manner in which this conventional system enters alphanumeric text is time-consuming and inefficient in that the user often must execute many (many more than six) button actuations in order to move the displayed cursor to a desired one of the displayed character representations.
Throughout this specification, the term "key" is used in a broad sense to include any key or button (whether having dedicated or programmable function) that is actuatable by a digit of a human user. Thus, "key" may be used herein (depending on the context) to denote a button of a hand controller of an ICTV or multimedia player.